Add Cursor agent CI fix workflow (#80)

## Summary
- Adds a GitHub Actions workflow that automatically attempts to fix CI
failures using cursor-agent
- When the test workflow fails on a PR, this workflow analyzes the
failure logs and proposes fixes via a compare link comment
- Modeled after the existing fix-ci workflow in the kernel monorepo

## Test plan
- [ ] Add `CURSOR_API_KEY` secret to the repository settings
- [ ] Verify workflow triggers on next CI failure

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Introduces automated CI remediation via `cursor-agent` when the `Run
tests for the CLI` workflow fails on PRs.
> 
> - New `.github/workflows/fix-ci.yaml` triggers on failed
`workflow_run` events and runs on `ubuntu-latest`
> - Installs `cursor-agent`, configures git identity, sets up Go from
`go.mod`, and uses `gh run view <id> --log-failed` for diagnostics
> - Generates minimal fixes, pushes to `ci-fix/<pr-head-branch>`, and
posts a PR-ready compare link as a comment
> - Scoped permissions: `contents`/`pull-requests` write, `actions`
read; avoids creating PRs directly and prevents duplicate comments
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
7f03716. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: masnwilliams

.github/workflows/fix-ci.yaml

@@ -0,0 +1,97 @@
+name: Fix CI Failures
+
+on:
+  workflow_run:
+    workflows: [Run tests for the CLI]
+    types: [completed]
+
+permissions:
+  contents: write
+  pull-requests: write
+  actions: read
+
+jobs:
+  attempt-fix:
+    if: >-
+      ${{ github.event.workflow_run.conclusion == 'failure' && 
+          github.event.workflow_run.event == 'pull_request' &&
+          github.event.workflow_run.name != 'Fix CI Failures' }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Install Cursor CLI
+        run: |
+          curl https://cursor.com/install -fsS | bash
+          echo "$HOME/.cursor/bin" >> $GITHUB_PATH
+
+      - name: Configure git identity
+        run: |
+          git config user.name "Cursor Agent"
+          git config user.email "cursor-agent@onkernel.com"
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          go-version-file: 'go.mod'
+
+      - name: Fix CI failure
+        env:
+          CURSOR_API_KEY: ${{ secrets.CURSOR_API_KEY }}
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          BRANCH_PREFIX: ci-fix
+        run: |
+          cursor-agent -p "You are operating in a GitHub Actions runner for the Kernel CLI repository.
+
+          The GitHub CLI is available as \`gh\` and authenticated via GH_TOKEN. Git is available. You have write access to repository contents and can comment on pull requests, but you must not create or edit PRs directly.
+
+          # Context
+          - Repo: ${{ github.repository }}
+          - Workflow Run ID: ${{ github.event.workflow_run.id }}
+          - Workflow Run URL: ${{ github.event.workflow_run.html_url }}
+          - Fix Branch Prefix: ci-fix
+
+          # Codebase Structure
+          - cmd/ - CLI commands (main command implementations)
+          - cmd/proxies/ - Proxy-related commands
+          - cmd/mcp/ - MCP server commands
+          - pkg/ - Supporting packages and templates
+          - Makefile - Build and test targets (\`make test\` runs \`go vet\` and \`go test\`)
+
+          # Goal
+          Implement an end-to-end CI fix flow: identify the failing PR, analyze the failure, make minimal targeted fixes, and propose changes back.
+
+          # Requirements
+          1. Use \`gh run view ${{ github.event.workflow_run.id }} --log-failed\` to get failure logs
+          2. Identify the PR associated with the failed workflow run
+          3. Analyze the failure - common issues include:
+             - Go compilation errors
+             - Test failures (missing interface methods, type mismatches)
+             - Mock/fake implementations missing new interface methods
+             - Linting issues from \`go vet\`
+          4. Make minimal, targeted edits consistent with the repo style
+          5. Create/update a fix branch: ci-fix/<pr-head-branch>
+          6. Push changes and post a PR comment with ONLY a compare link for quick PR creation
+             - Format: Describe the fix, then provide ONLY a single PR creation link
+             - Example format:
+               \"🔧 CI Fix Available
+               I've pushed a fix for the CI failure.
+               
+               👉 Click here to create a PR with the fix\"
+             - Do NOT include any git merge instructions or manual merge commands
+             - Only include the compare link (e.g., https://github.com/.../compare/...)
+
+          # Style Guidelines
+          - Go: Follow existing patterns, use testify for tests
+          - Comments: Keep simple, no extra formatting
+          - Interfaces: When adding methods to interfaces, update all implementations including test fakes
+
+          # Constraints
+          - Do NOT create PRs directly - only post comments with compare links
+          - Avoid duplicate comments - update existing bot comments
+          - If no actionable fix is possible, make no changes and post no comment
+          - PR comments must ONLY include the PR creation link, no manual merge instructions
+          " --model opus-4.5 --force --output-format=text